Compensating-gear mechanism



C. W. HARROLD COMPENSATING GEAR MECHANISM FiledMarch 28, 1924 Aug. 21,1928.

Patented Aug. 21, 1928.

UNETEDSTATES PATENT OFFICE.

CHARLES N. HABROLLD, OF CLEVELAND, OHIO, ASSIGNOB, BY MESNE ASSIGNMENTS,

'IO HARRIS-SEYBOLD-POTTER COMPANY, OF CLEVELAND, OHIO, A CORPORATION OFDELAWARE.

comrnnsarmecnan MECHANISM.

Application filed March 28, 1924. Serial No. 702,547.

My invention relates broadly to compensating mechanisms to be associatedwiththe connecting gears of a pair of rotating members or elements inwhich the driven member may be allowed to rotate independently of itsgear in at least one direction when such. member is being actuated byrolllng contact wit-h the driving member.

Such compensating gear mechanism' involving my invention may be utilizedin many and widely different kinds of machinery in which such coactingrotary members are to be operated with requisite compensation orflexibility between the coact-ing gears carried by such membersparticularly whenv and their respective cylinders showing the suchcoacting members are driventhrough frictional contact or otherwise thanthrough such engaging gears.

A preferred use of my invention is embodied in rotary printing machineryin which two cylinders are arranged in mutually parallel relationshipwith one cylinder having a drive gear in mesh with a. compensating gearcarried by the driven cylinder which is allowed to travel to a limitedextent in either direction relatively to the rotation of its gear duringdifferent portions of their cycle.

The aim of my invention is, amongother things, to provide a compensatinggear mechanism of this character which is certain and precise in action,simple in construction, and by which the various objects hereinbeforenamed and others can be effectively accomplished without in any wayaffecting the accuracy of the predetermined relation of the twocylinders, irrespective of their speed of rotation. To this end myimproved gear mechanism as applied to printing-presses provides that ata certain point in the driven cylinder cycle, such cylinder and its gearare brought into predetermined relation or register; for example, at thebeginning of the a pair of coacting cylinders from slipping on eachother when rolling together, which slipping would cause injurious wearon the printing surfaces and marks or streaks in the printing. Suchslipping is always likely to/ plied to other forms of machinery inwhich.

compensating gear mechanisms of this char:

acter are required or highly desirable to-ensure eifective operation.

In the accompanying drawlngs, Fig. 1 is a partial end elevation of thecoacting gears use of my-improvement in one of the several forms ofembodiment in connection with a rotary printingpress; i

Fig. 2 is a partial side view of one of the cylinders equipped with thecompensating gear mechanism; and

- Fig. 3 is an enlarged sectional view taken on the line3--3 of Fig. 2looking in the direction of the arrows.

Similar numerals refer to similar parts throughout the several figures.

Referring to the drawings, the gear 4 is rigidly secured to the drivingcylinder 5 in which the peripheral surface or bearer line 'is indicatedby the dotted line Gin Fig. 1. such gear being rotated in the directionof the arrow shown in Fig. 1. The gear 4: engages and drives the gear 7carried by the driven cylinder 8. The gear 7 is secured to the cylinder8 by. cap-screws 9 passing through elongated slots 10. the screws beingthreaded into the'endv of. the cylinder 8 as shown in F ig; -2. Theslots 10 and the heads 11 of the cap-screws 9 provide a suitableclearance (Fig. 2) with the gear 7 to permit the latter to have. alimited rotation independent of the cylinder 8.

Also affixed to the cylinder 8 is the central stud 12 projecting throughthe elliptical. slot 13 formed in the gear 7. The head 14 of the stud 12projects slightly above the outer surface of the gear"? as shown in Fig.3 to provide the necessary clearance. Threaded to the gear 7 is thebracket 15 having the smoothed bore 16 through which passes the threadedbar 17 having its tip 18 engaging the socket 19 formed in one side ofthe head 14 thereby providing a fixed registering stop as shown in Fig.3. Coiled about the bar 17 is the heavy compression driving spring 20,one end of which bears against the inner side of the bracket 15 whilethe other end bears against the adjusting collar21 threaded on the bar17 the collar 21 being held in position by the locking-nut 22. Lockingnuts 23 and 24 are threaded on the outer end of'the bar 17 outside thebracket 15 as shown.

Also threaded to the gear 7 opposite the central stud 12 is the bracket25 having the threaded bore 26 in which is threaded the screw-bar 27held in any predetermined position in the bracket 25 by set-screw 28. IInside the bracket 25 the adjusting collar 29 is threaded on the bar 27and coiled about the inner end of the bar 27 is the light reactingspring 30, one end bearing against the collar 29 and the other endbearing" against the inclined face 31 formed on the head loppositethe'socket 19. The peripheral surface 32 or bearer line of the cylinder8 (Fig. 2) is also indicated by the dotted line 3232 in Fig. 1.

The operation of my compensating gear mechanism as shown when embodiedin a rotary printing-press in printing sheets is substantially asfollows: When the gear 4 is driving the cylinder 8 through the gear 7driving spring 20 and bar 17 bearing on the stud 12, such heavy spring20 is designed to take care of any jars or shocks greater than thenormal driving load, while permitting the cylinders 5 and 8 to rollequally together. Under certain conditions the spring 20 may be presseddown until entirely compressed and so form a. solid or rigid drive forthe stud 12 fastened to the cylinder 8. However, I have found that theuse of such heavy coil spring 20 so adjusted and set that it willnormally drive the cylinder 8 without further 7 compression is desirableas an additional safeguard against abnormal jars or shocks which mightdisturb the rolling contact of i the cylinder bearers 6 and 32.

mechanism is performed by the reatcing spring 30 which is lighter thanspring 20 and is so adjusted by the collar 29 that its compression isless than the frictional powerof the two cylinders 5 and 8 through theirbearers 6 and 32 respectively when rolling together. During the printingportion of the revolution, the cylinder 8 has a tendency to be drivenfrom its coacting cylinder 5 through frictional contact of theperipheral surfaces 6 and 32 extending longitudinally throughout thesurfaces of the cylinders. While so rolling together, any inequality ofcylinder diameter or irregularity of the meshing teeth in the gears 4Cand may cause the cylinder 8 torun ahead of the gear 7, and immediatelythe spring 30 will yieldso as to allow a true rolling contact to bemaintained between the cylinder surfaces 6 and 32 until the printing ofthe sheet is completed. In

the balance of the revolving cycle, the cylinder surface 32 may bedepressed or cut away for a short segment 33 as shown in Fig. 2 withrespect to'the cylinder 5 so that this rolling contact does not exist;during this period of travel the force of the reacting spring 30 bringsthe cylinder 8 back with the tip 18 of the bar 17 in full contact withthe socket 19 formed in the stud 12, or back to its normal predeterminedposition in readiness to begin the next printing revolution with therolling contact drive between the two cylinder surfaces 6 and 32.

It will therefore be observed that the spring 30 automatically functionsto retard the cylinder 8, or hold the stud 12 against the tip 18 of thebar 17 ,at all times to secure proper relation of the cylinders, exceptwhen the force of such spring 30 may be overpowered by the drivingeffect produced by the frictional engagement of the cylinder bearers 6and 32; and further that suchspring 30 immediately brings the cylinder 8back against a fixed stop at proper relation with the cylinder 5 readyfor thebeginning of the printing surface contact, as soon as theoverpowering frictional drive from rolling contact of the coactingcylinders 5 and 8 ceases at the end of the previous printing operation.Hence the underlying feature or principle of my improvement lies inproviding a compensating gear mechanism which will allow the drivenrotary member or cylinder to rotate independently of its gear in atleast one direction during that part of its cycle when such member maybe driven from another source of power. a I

While the construction herein shown and described embodies the inventionin a preferred form, it will be understood that changes and variationsmay be made in the various parts andtheir arrangement with out departingfrom the principles and scope 'of the invention or sacrificing its chiefad- The chief function of my compensating vantages. V

I claim as my invention '1. In a compensating gear mechanism, a rotarydriven member, a drivegear carried thereby, means comprising a spring ofheavy compression between sa'id member and gear to rotate the member inone direction, a spring connection of relatively less compres sionbetween said member and gear to bring the former into normal rotaryrelation with the gear whenever said member is rotated out of saidrelation in an opposite direction, and means for adjusting thecompression of either of said springs independently of the other.

2. In combination, a drive gear, a coacting driven gear, a rotary membercarrying said driven gear and set to rotate in predetermined relationwith said driven'gear. a spring of heavy compression between said drivengear and member to rotate the latter in one direction, means forrotating said member apart from both said gears, and means foryieldingly allowing said member to have an opposite movement withrespect to said driven gear only when driven separately by saidmember-rotating means.

3. In combination, a drive gear, a coacting driven gear, a rotary membercarrying said driven gear and set to rotate in predetermined relationwith said driven gear, a spring of heavy compression between said drivengear and member to rotate the latter in one direction, means forrotating said member in the same direction apart from both said gears,and means for yieldingly allowing said memher to have an oppositemovement with respect to said driven gear only when driven separately bysaid member-rotating means.

4. In combination, a drive gear, a coacting driven gear, a rotary membercarrying said driven gear and set to rotate in predetermined relationwith said driven gear, a spring of heavy compression between said drivengear and member to rotate the latter in one direction, means forrotating said member apart from both said gears, and a spring of lesscompression for yieldingly allowing said member to have an oppositemovement with respect to said driven gear only when driven separately bysaid member-rotating.means.

5. In combination, a drive gear, a coacting driven gear, a rotary membercarrying said driven gear and set to rotate in predetermined relationwith said driven gear, a-spring of heavy compression between said drivengear and member to rotate the latter in one direction, means forrotating said member in the same direction apart from both said gears,and a spring of less compression for yieldingly allowing said member tohave an opposite movement with respect to said driven gear only whendriven separately by said member-rotating means.

6. In combination, two coacting rotary members, a drive gear associatedwith one of said members, resilient means arranged between said gear andits members for normally rotating the latter in predeterminedly yieldingrelation with said gear, and a yielding connection between said gear andsaid driven member to allow the latter to have an opposite movement withrespect to said gear only when rotated by the other rotary member.

7. In combination, a drive'gear, a coacting driven gear, a rotarycylinder loosely carrying said driven gear connected thereto to rotatein predetermined relation therewith, a yielding connection of heavycompression between the driven gear and cylinder to rotate the latter inone direction, means for rotating said. cylinder apart from both saidgears, and means for yieldingly allowing said cylinder to have anopposite movement with respect to said driven gear only when separatelydriven by said rotating means.

8. In combination, two coacting rotary cylinders, a drive gearassociated with one of said cylinders, resilient means arranged betweensaid gear and its cylinder for normally 7 rotating said cylinder inpredeterminedly yielding relation with said gear in one direction, and ayielding connection between said gear and said driven'cylinder to havean opposite movement with respect to the gear only when actuated by theother cylinder.

9. In combination, two coacting rotarycylinders, a drive gear associatedwith one ol said cylinders, means between said gear and its cylinder.for normally rotating the latter in one direction, and means forallowing said driven cylinder to rotate independently of the gear whenactuated by the other cylinder, said last means restoring the normalrelation of said gear and cylinder when the latter is not actuated bythe other cylinder.

10. In combination, a pair of rotary cylinders having their surfaces inrolling contact during part of their cycle, a drive gear carried by oneof said cylinders, a yielding connection between said driven gear andits cylinder to rotate the latter when the cylinders are out of contact,and means for allowing said driven cylinder to rotate independently ofits gear when said cylinders are brought into rolling contact.

11. In combination, a pair of rotary cylinders having their surfaces inrolling contact during part of their cycle, a drive gear carried by oneof said cylinders, a yielding connection between said driven gear andits cylinder to rotate the latter when the cylinders are out of contact,and means for allowing said driven cylinder to rotate independently ofits gear in one direction when said cylinders are-brought into rollingcontact and in the opposite direction when said cylinders are out ofrolling contact.

12. In combination, two coacting rotary cylinders, a drive gear carriedby one of said cylinders and rotatable independently thereof, aconnect-ion between said gear and its cylinder for driving the latter inpredetermined relation with the gear, means for actuating said cylindersin unison independently of said drive gear, and means for yieldinglyholding said gear in operative relation with its cylinder while saidcylinders are actuated in unison to restore the predetermined relationwhen said cylinder is again driven by its gear.

13. In combination, two coacting rotary cylinders, a drive gear carriedby one of said cylinders and rotatable independently thereof, a yieldingconnection between said gear and its cylinder for driving the latter inpredetermined relation with the gear, means for actuating said cylindersin unison independently of said drive gear, and adjustable means foryieldingly holding said gear in operative relation with its cylinderwhile said cylinders are actuated in unison to restore the predeterminedrelation when said cylinder is again driven by its gear. t

14:. In combination, a rotary member, a coactin drive gear carried byand in predeterminec relation with said member, means comprising ayielding connection between said member and gear for normally rotatingsaid member in one direction, and a separate yielding connection ofrelatively less compression and said first yielding connectionpermitting said member to rotate in the same direction independently ofsaid gear only when said member is separately actuated apart from thegear, said last yielding connection restoring the normal predeterminedrelation between said member and gear when the former is no longerseparately actuated.

15. In combination, a rotary member, a drive gear connected thereto inpredeterminedly yielding relation, separate means for rotating saidmember at an increased speed, and spring connection acting only in onedirection for restoring predetermined relation between said member andsaid gear whenever said rotating means is out of operative engagementwith said member.

. CHARLES W. HARROLD.

